This invention relates generally to hydrotherapy and more particularly to an improved method and apparatus useful in spas, hot tubs, bathtubs, and the like for discharging a fluid (e.g. water-air) stream while concurrently causing the stream to travel across an area so as to impact against and massage an area of a user's body.
Applicants' U.S. Pat. No. 4,679,258 discloses a method and apparatus for discharging a fluid stream, while concurrently causing the stream to travel along a substantially random path. A user is thus able to fixedly position his body proximate to the apparatus to enable the discharged stream to impact against and sweep over an area of the user's body. In a typical application, the apparatus is mounted in an opening in the peripheral wall (i.e. including floor) of a spa, hot tub, bathtub, etc., generically referred to as a water tub.
A preferred embodiment of the travelling discharge hydrotherapy apparatus disclosed in said U.S. Pat. No. 4,679,258 is characterized by the use of a water-air jet assembly including a nozzle for discharging a water jet under pressure into a mixing cavity. The water jet creates a suction, via venturi action, which draws air into the cavity and the resulting water-air stream is then discharged into an elongated rigid conduit having supply, intermediate and discharge sections. The conduit is open at both ends having a supply orifice at its supply section end and a discharge orifice at its discharge section end. The supply section outer wall is shaped to form a ball having a central bore defining said supply orifice. The ball is accommodated for swivel movement within a socket with the supply orifice open to the aforementioned mixing cavity. The conduit discharge end is left free to travel across a substantially planar travel area roughly approximating an extension of the tub wall. The water-air stream is discharged from the discharge orifice in a direction having a primary massage component extending substantially perpendicular to the travel area and having a secondary thrust component extending substantially parallel to the travel area. The thrust component produces a lateral force for moving the discharge end along a path lying within said travel area. The boundary of the travel area is substantially defined by a thrust modifier means in the form of a frame, which cooperates with a pivot pin secured to the conduit. The frame includes a series of open recesses, each intended to momentarily capture the pivot pin, as the conduit discharge end moves toward the area boundary. With the pivot pin so captured, the stream thrust component acts to rotate the discharge end around the pivot pin and thereby redirect the thrust component enabling the pivot pin to withdraw from its open recess and initiate a new traverse across the frame.
Thus, the discharge orifice will traverse a path comprised of small substantially semicircular path segments, each described when the pivot pin is engaged in a recess, linked by longer translational path segments extending between recesses. The translational recess-to-recess path segments extend substantially across the frame and occur in an essentially random unpredictable pattern.
Applicants' U.S. Pat. No. 4,715,071 discloses a travelling discharge hydrotherapy apparatus in which a passageway is provided around the swivel mounting of the conduit supply end for passing tub water from outside the conduit into the mixing cavity. As discussed therein, this action mitigates the effect of the suction force produced in the mixing cavity acting on the conduit itself.
Applicants' U.S. application Ser. No. 170,718 discloses a hydrotherapy jet assembly for discharging a water stream through an adjustable flow director. The assembly is capable of operating in an air entrainment mode and/or a tub water entrainment mode and includes a single valve control member enabling a user to adjust the amount of air entrainment and/or water entrainment and/or supplied water jet to selectively vary the intensity of the discharged stream.